Call Your Congressmen: Pass The “Nogales Wastewater Fairness Act”!


A necessary first step in reaching a comprehensive solution to our ongoing border sewage/flood problems is to establish Federal responsibility for the IOI (“International Outfall Interceptor”), which runs for 9 miles from the Mexican border to the Nogales International Wastewater Treatment Plant in Rio Rico.

Right now (November 2017), our Senators and Congressmen have introduced bills in both Houses to do exactly this. However, both bills have been languishing in committees since March.

in the Senate: S. 551: “Nogales Wastewater Fairness Act”

  • Senator John McCain (who sponsored this bill): 520-670-6334
  • Senator Jeff Flake: 520-575-8633
  • Senator Bob Corker (Chair of Committee on Foreign Relations, where bill currently sits): 202-224-3344

in the House of Representatives: H. R. 1410: “Nogales Wastewater Fairness Act”

  • Congresswoman Martha McSally (who sponsored this bill): 520-881-3588
  • Congressman Raul Grijalva (co-sponsor): 520-622-6788
  • Congressman Garret Graves (Chair of Subcommittee on Water Resources and Environment, where bill currently sits): 202-225-3901

Please call these public servants and urge them to move these bills!

Just call (much more influential than an email or letter), you can leave a message. Here are some things you could say:

  • I am very concerned about protecting my drinking water and public health here at the AZ/Mexico border.
  • I am a constituent (if you are).
  • We need federal attention to our border sewage and flood problems before we have another international sewage disaster.
  • Please get the Nogales Wastewater Fairness Act out of committee so it can be passed!
  • Thank you for your action on this important issue (and Friends of the Santa Cruz River thanks you!)

FOSCR Statement on the Recent Rupture of the IOI

Friends of the Santa Cruz River logo

Friends of the Santa Cruz River has been concerned for some time that the binational sewage pipe, the International Outfall Interceptor (IOI), could be breached by floods in the Nogales Wash under which it lies. A pipe break would spill raw sewage into the communities of Nogales, Rio Rico, Tubac and further north along the Santa Cruz River. Our warning is encapsulated in a short video we had made and started distributing earlier this year, called “Flirting With Disaster“.

We are sad to say this eventuality has now come to pass. The waters of the Wash and the Santa Cruz River into which it flows are now heavily contaminated. An easy fix is not in sight; and even when repairs to this breach are eventually made, there is a good likelihood that a similar disaster will happen again somewhere else along the 9-mile IOI, possibly even this summer.

Although the International Boundary and Water Commission (IBWC) has developed a plan to insert a resin sleeve into the existing IOI, and FOSCR supports this repair strategy, it will not solve the persistent problem of the location of the IOI.

This binational sewage pipe must be removed from the bed of the Wash if future public health disasters like this one are to be avoided in the future. IOI relocation will not come cheap or easy. However, barring a major overhaul of the entire Nogales Wash watershed (most of which is in Mexico), repeated erosive floods will inevitably threaten the IOI with rupture and thus threaten the health of all Santa Cruz County residents as well as the ecological health of the Santa Cruz River ecosystem. Furthermore, since most of Santa Cruz County’s residents depend for their drinking water on the aquifer that underlies the river, our drinking water supply also faces a long-term and significant threat from repeated discharges of contaminated water into the river.

This is a matter of true national security; if we don’t have clean drinking water and are not protected from public health threats, how secure are we? The IBWC must take responsibility for this border crisis and first, repair the IOI. But second and more importantly, they must get the IOI out of the Nogales Wash.

Nogales Wash

Nogales Wash and Climate Change

Article written by FOSCR Board member Ben Lomeli

Nogales Wash
Nogales Wash emerging from a tunnel in Nogales, AZ. Photo by Hans Huth.

Every storm that hits Nogales, AZ puts pressure on the deteriorating sewage pipe that carries 14 million gallons of sewage daily, mostly from Mexico, right through the small city of Nogales, AZ to the Nogales International Wastewater Treatment Plant (NIWTP) in Rio Rico, AZ.

This pipe, the International Outfall Interceptor (IOI), was constructed in 1971. Its path to the NIWTP lies mostly under the Nogales Wash. It is protected from erosive flood flows by the concrete-lined floor of the Wash and several feet of dirt.

Because of upstream urbanization and its deteriorated condition, the IOI is in danger of becoming exposed and bursting every year during heavy summer monsoon flood flows in the Nogales Wash. Additionally, the IOI continues to leak raw sewage into the groundwater aquifer system that provides drinking water for most of the community.

Friends of the Santa Cruz River commissioned a short video documenting the IOI problem to inform as many people as possible and to create a unified voice to urge federal decision makers to fund a proper repair for this failing infrastructure complex. This film can be viewed on the website.

The Nogales Wash is located in an arid-semiarid desert landscape. It lies within the Upper Santa Cruz River Basin in southeastern Arizona. There are two major precipitation periods in the typical southeastern Arizona water year. The first and most dramatic is the summer monsoon season (July–Sept), in which 50% of annual precipitation occurs. A secondary wet season during the fall and winter months is caused by Pacific frontal storm movement.

Potential climate change-related impacts are of concern for Nogales Wash (and the IOI) because all credible predictions are for warmer and drier conditions overall, but with less frequent but more intense storms.

Detention basins constructed in Mexico are too few, too small (appear to be designed for about a 25-year storm), and have quickly filled up with sediments. Many more are needed and all need to be regularly maintained. Watershed improvements are also needed to stabilize eroding soils and thus reduce excessive sediment flows. Revegetation of bare soils, water-harvesting, erosion control, retro-fitting of stormwater BMPs (Best Management Practices) and LID (Low Impact Development) approaches would all help reduce stormwater peak flows and excessive sediment transport.

Therefore, as long as the contributing watershed in Mexico continues to produce abrasive sediment-laden peak flows that far exceed the conveyance capacities of Nogales Wash, all our local stormwater infrastructure remains at risk. As long as the IOI remains underneath the deteriorated unstable and undersized Nogales Wash, the threat of IOI ruptures remains a reality that will most likely be increased by climate change.

NOTE: A version of this article was also published in “Canyon Echo,” Sierra Club Arizona”s Summer 2017 Newsletter. Click to download a .pdf of the article found on page 11.